Brake control system



Jan. 3, 1939. J. H. COYLE BRAKE CONTROL SYSTEM Filed Feb. 25, 1937 3 Sheets-Sheet l 1311.3, 1939. J, H, COYLE 2,142,631

BRAKE CONTROL SYSTEM Filed Feb. 25, 1937 3 Sheets-Sheet 2 J ai .6 s? 1041050 fil/U 55 64 J 357 o a 7L 6 116 Il @y E FJ 127 V150 73 7o 6'3 d3 1 12,1628 ,f s:

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Jan. 3, 1939. J. H. coYLE 2,142,631

BRAKE CONTROL SYSTEM Filed. Feb. 25, 1937 3 Sheets-Sheet 3 j (gru) Patented Jan. 3, 1939 PATENT GFFICE nanna coN'raoi. SYSTEM Joseph H. Coyle, Long Hill, Conn., .assinor to Joseph H. Coyle, III, Philadelphlara.

Application February 25, 1937, Serial N0. 127,612

12 Claims.

This invention relates to ,brake control systems,

and more particularly to a system adapted to effect an application of the brakes under certain predetermined conditions and to eiect a release of the brakes underother predetermined conditions. This invention also relates to systems ior use in facilitating the starting of an automobile when the same has been brought to rest on an upward incline with the brakes applied.

Considerable diillculty is sometimes encountered in handling an automobile on an upward incline. This occurs not only when the vehicle has been stopped at a trafc light or for some other cause, at which time the automobile may tend to roll backwards, but also upon starting the car into motion. This difllculty arises primarily because of the necessity, with practically all the automobiles now in use, for actuating the clutch release pedal with one foot, releasing the brakes of the vehicle either with the other foot or by hand while at the same time actuating the accelerator pedal to supply additional fuel to the engine for the increase starting torque.

It is an object of the present invention to provide a brake control system which will under certain conditions apply the brakes oci the vehicle and maintain the brakes in an applied position, subject to the control of the operator of the vehicle.

It is a further object of the present invention to provide a brake control system which is effective under certain predetermined conditions to release the brakes of an automobile upon the actuation of the accelerator pedal.

It is a further object of the present invention to provide a brake control system for automobiles which includes a control element responsive to the inclination of the automobile.

'It is a further object of the present invention to provide a brake control system which will exert, one character of control when the car is on the level or with the front end inclined downwardly, and which will exert a different character of control when the vehicle faces upwardly on a hill.

It is a further object of the present invention to provide av structure for controlling the application and release of the brakes of a motor vehicle which structure utilizes the vacuum created in the intake manifold of the vehicle.

Other objects of the present invention Will appear from the annexed specification and claims.

The nature and characteristic features of my invention will be more readily understood from the following description, taken in connection suitable for this purpose.

with the accompanying drawings forming part thereof in which:

Figure 1 is a side elevational view of a preferred embodiment of the invention;

Fig. 2 is a side view of the device shown in Fig. l partly in elevation and partly in vertical section, and illustrating certain details of the construction of the cylinder and piston;

Fig. 3 is a top plan view ofthe device shown in Fig. 1, part of the valve housing being broken away to show the internal construction thereof;

Fig. 4 is a fragmentary vertical sectional view taken approximately on the line 4-4 of Fig. 3, anduillustrating the eifect of the inclination on a hi Fig. 5 is a vertical sectional view taken approximately on the line 5-5 of Fig. 3;

Figs. 6 and 7 are fragmentary vertical sectional views taken respectively on the line 8-6 of Fig. 3, showing different positions of two of the control valves;

Fig, 8 is a horizontal sectional view taken approximately on the line 8-8 of Fig. l;

Fig. 9 is a side elevational view of one o! the control valve members removed from the valve housing;

Fig. 10 is an enlarged fragmentary sectional view taken approximately on the line l0-I0 o! Fig. 2, and illustrating the construction of the compensating valve;

Fig. 11 is an enlarged fragmentary sectional view taken approximately on the line Il-ll of Fig. 2, and illustrating the construction of the atmospheric check valve; and

Fig. 12 is a diagrammatic view of the system of the present invention illustrating the manner in which the control of the vehicle brakes is eected.

It will, of course, be understood that the description and drawings herein contained are illustrative merely, and that various modications and changes may be made in the structure disclosed without departing from the spirit of the invention.

Referring more particularly to the drawings, the control system of the present invention includes a cylinder I5 which may be secured to a portion of the frame or body (not shown) of the automobile in any suitable manner, although a stud I6, extending through a bracket ll secured in the end of the cylinder l5, has been found The longitudinal or horizontal axis of the cylinder I5 is preferably disposed so as to be parallel with the longitudinal or horizontal axis of the vehicle. The cyl-` inder I5 may be of any Preferred construction, but a cylinder having an end wall I5 facing toward the front end of the vehicle and illustrated as to the left in the drawings, and a aide wall as at i5 integral with the end wall I5, has been found satisfactory.

The other end of the cylinder I5, which faces toward the rear end of the vehicle and is illustrated as to the right, is closed by a cylinder head 25, suitable packing being provided as at 2i. The cylinder head 20 is provided with a plurality of inwardly extending fingers 22 for limiting the movement of the piston, as hereinafter pointed out.

An atmospheric check valve 23 which is shown in detail in Fig. 11 is provided in the cylinder head 20, to open outwardly. The check valve 23 is normally held seated by a spring 24, and a nut 25 on the valve stem 25 provides for adzo justment of the force applied by the spring 24 'so that the opening of the valve 23 is suitably controlled, as hereinafter more fully referred to. A screen 21l may be provided adjacent the valve 23.

A suitable protective cover 35 which does not interfere with the operation of the check valve 23 may be mounted externally with respect to the cylinder head 20, the cylinder head and cover being held in position by a plurality of hooked clamping members 3i in engagement with the cylinder head 20, the other ends of the clamping n members 3| extending through a spider 32 at the opposite end of thecylinder I5. 'I'he hooked clamping. members 3i are heldin assembled relationship by nuts 33 which bear on lock washers 34 in contact with the arms of the spider 32.

A piston 55 is mounted within the cylinder I5 for reciprocal movement therein, this piston 35 being composed of dished plates 35 and 31 which are held together by nuts 35 and 35 on a piston rod 40, and carry at their outer edges a suitable expansible packing 4i and a suitable packing leather 42 which is pressed outwardly and into contact with the internal wall of the cylinder I5 by a circular leaf spring 43. A spiral spring 44, the convolutions of which may rest one within another, is mounted at the left hand portion of the cylinder I5 between the end wall I5 and the plate 35 of the piston 35, and normally exerts a force on the piston 35 tending to move the piston 35 towards the right, as illustrated in the drawings.

Movement of the piston 35 into contact with the cylinder head 25 is prevented by the fingers 22. To the left hand face of the piston 35 there is also secured an annulus 45 of felt or similar material which prevents the piston 35 from striking or coming into contact with the end wall I5 of the cylinder I5. The piston rod 45 extends through a suitable packing 45 in the cylinder head 20.

The piston rod 45 is provided with a passageway 41 which communicates freely at its left hand or forward end through suitable openings 45 with the space at the right hand or rear side of the piston 35. The piston rod has threaded on its outer extremity a sleeve 55 which is locked in position with respect to the piston rod by a nut 5I. The sleeve 50 has apertures 32 therein, so that the passageway 41 may be connected to the atmosphere under certain predetermined conditions.

A compensator valve 55 is mounted within the sleeve 55 and seats against the end of the piston rod 45 in such a manner as to normally cut oil amasar communication between the apertures 52 and the passageway 41. The head 5I oi' the compensator valve 55 has a rod 52 secured thereto to which asmaller rod 53 is connected, the rod 53 having threaded thereon a clevis 54 for connection by a rod 55 with the brake mechanism. shown diagrammatically at 55 and 51, of the brake system of the vehicle, as hereinafter more fully pointed out. The compensator valve 55 is normally held seated by a spring 55 which bears at its outer extremity in a compensator valve adjusting sleeve 55 which is threaded within the sleeve 55, may be turned by means of the end portion 1l, and is adapted to be locked by means of a lock nut 1I in a position to provide the desired force on the spring 55. The spring 55 is adapted to be compressed by a force applied to move the piston 35 to the left, the force on the spring in the opposite direction being derived from the force necessary to apply the brakes.

'I'he cylinder head cover 35 is provided with a rim portion 12 for the reception of one end of a sleeve 13 of rubber or other suitable material for keeping the piston rod 40 from becoming coated with dirt or mud. 'I'he sleeve 13 may have suitable apertures 13a therethrough to permit air to pass to the interior of the sleeve, although if the apertures are omitted leakage past the ends of the sleeve will be sufcient. The other end of the sleeve 13 is received in an annular slot 14 in the sleeve 55.

The structure for pneumatically controlling the movement of the piston 35 within the cylinder I5, and thereby controlling the release of the brakes, may be of any preferred type, but preferably provides for three types of control. These types of control preferably include a control operable from the dash board or instrument panel, a control operable from the accelerator pedal of the vehicle, and a control responsive to the inclination of the vehicle.

In the embodiment of the invention herein disclosed, the dash board control valve and pedal control valve are enclosed in a valve housing 55. The housing 55 is mounted above the cylinder I5 on a boss 5I which extends outwardly from the end of the cylinder I5.

The valve housing is secured to flared portions 52 of the boss 5| by means of bolts 53 which also serve to hold in position a mounting bracket 54.

The upper side of the valve housing 50 is provided with a coupling portion into which an elbow 55 is threaded.

'I'he elbow 55 is connected by suitable tubing 51 to the intake manifold of the motor of the vehicle, shown diagrammatically at 55 in Fig. 12, or to any other suitable source of suction. The elbow 55 may, if desired, although it is not essential, be provided with a check valve 55 responsive to and opening when there is a vacuum in the line 51, and shutting oif flow from the conduit 51 when the pressure therein rises to that of the atmosphere. A passageway 55 within the elbow 55 communicates with a port 5I in the valve housing 50, as will be seen more clearly from Figs. 6 and 7.

The dash board control mechanism includes a dash board control valve 52 which is mounted within the valve housing 50 and preferably includes a slide valve member in the form of a rod, movable along a valve receiving space 53 in the housing 50, and manually operable from the dash board oi the vehicle. A wire 54, enclosed in a flexible protective covering 55 is employed for operating this valve and may be attached thereto the end of the valve member 92 and clamping the wire by means of a screw and lock nut 96. A suitable handle 91 is mounted on the dashboard. shown diagrammatically at 93, for manually operating the cable wire 94.

A support for the end of the encasing portion of the flexible covering 95 is provided and includes abracket 99 having an end portion carrying a screw clamp |00, the other end portion of the bracket 99 serving as a cover plate for the end of the valve housing 80. A packing ring |0| is inserted between the end of the valve housing 80 and the bracket portion 99, and screws |02 are provided for holding the bracket 99 in position.

The valve housing 80 has a chamber |03 therein which is closed at the end by the cover plate 99. The chamber |03 is in communication with the atmosphere through a passageway |04 (see Figs. 3 and 5) which permits the entrance of air at atmospheric pressure, or the exhaust of air therethrough, a screenl |05 being mounted in this passageway for preventing the entrance of dirt into the system.

The valve casing 80 has a port |06 disposed on the opposite side of the valve receiving space 93 from the port 9|. The slide valve 92 is provided with a passageway as at |01 for affording communication between the port 9| and the port |06, under certain conditions and when it is desired to have the brake control system effective. The slide valve 92 is likewise provided with a passageway as at |08 which communicates with the chamber' |03 in the valve housing 90, and is adapted under certain conditions of operation and when it is desired not to utilize the brake control system, to be brought to a position to connect the port |06 through the chamber |03 with the atmosphere.

It will be seen that the slide valve 92 may be moved to either control position, as desired, by means of the handle 91.

The valve housing 80 is also provided with a second valve receiving space |03. The valve receiving space |09 is provided with a port |'0 which is oppositely disposed with respect to the port |06 and in alinement therewith. On the side of the valve receiving space 09 and spaced from l the port ||0, a square side port is provided,

the purpose of which will be hereinafter more fully referred to. Suitable vent ports ||2 may be provided in the valve housing at the ends of the valve receiving spaces 93 and |09.

The accelerator pedal control valve mechanism includes a control valve ||5 mounted within the valve receiving space |09, the valve member ||5 preferably being in the form of a rod and having suitable passageways therein. This valve rod l I5 is connected by an operating rod ||6 to the accelerator pedal arm ||1, the arm ||1 also being connected as by a rod ||8 to a throttle valve 20a on a carburetor |20, so that the valve member ||5 is actuated in-unison with the accelerator pedal ||1. The valve member 5 is provided with a passageway |2| which may be moved to a position for alinement between the port |06 and the port I |0.

The valve member ||5 is also provided, in the under side thereof, with a groove |22 forming a passageway, which is adapted to be moved by the actuation of the valve member ||5, into a position in communication with the port ||0.

The outer portion of the groove |22 communicates with the chamber |03 in the valve housing 90 and therethrough with the atmosphere. The

valve 'member ||5 is also provided on the side thereof with a second groove |23 which provides a passagewayfor lcommunication with the side port The end of the groove |23 may be rather shallow for the purpose of restricting the ilow past this point when the extremity of the groove |23 is moved past the edge of the port The groove |23 also communicates at its other end with the chamber |03 in the valve housing 80, and communicates withthe groove |22 by means of a slot |24.

The port I0 in the valve housing 90 communicatesthrough a passageway |25 in the boss 3| with the left hand end of the cylinder |5.

A coupling boss |26 is provided on the valve housing 80 and has therein a passageway in communication with the side port A pipe |21 is secured in the coupling boss |26 preferably by means of a threaded coupling member |28.

The bracket 84, referred to above, has mounted thereon the structure which provides a control responsive to the inclination of the vehicle. This control mechanism will be hereinafter referred to as a pendulum control mechanism by reason of its manner of operation.

The pendulum control mechanism preferably includes a generally triangular casing |30 which is mounted on the bracket 84 by means of bolts |3|. Acover |32 is removably secured on the lower end of this casing |30 by spring hooks |33. The upper end of the pendulum control casing |30 has mountedtherein a bearing pin |34 on which a pendulum member is swingably supported for movement within the connes of the casing |30.

'Ihe pendulum member |35 includes a forked portion |36 and a lower end portion |31 weighted with lead or other suitable material. The lower end |31 of the pendulum member |35 is preferably provided with a strip of felt |38 and a retaining strip of metal |39 which are mounted at right angles with respect to the longitudinal axis of the pendulum member |35.

The end portions of the felt strip |38 are adapted upon movement of the pendulum |35 about the axis furnished by the bearing pin |34, to contact the lower inner walls of the casing |30 and cushion the movement of the pendulum member |35, as well as provide' limits for the movement thereof. It will be noted that when the vehicle is level, the pendulum |35 will tend to assume the position shown in Fig. 1 and that an oscillatory or chattering movement thereof will take place, as hereinafter referred to. When the front end of the vehicle is elevated the pendulum will swing about its axis |34 and tend to assume a different position with respect to the casing |30, as indicated in Fig. 4. 4

The pendulum casing |30 has an outwardly extending portion |40 within which there is provided a pendulum valve chamber |4I. At the side of the portion |40 which faces away from the cylinder |5, a coupling |42 is provided which bas a passageway therein. 'I'he coupling |42 is threaded into the outwardly extending portion |40 and the passageway therein is in communication with a port |43.

The pipe |21, connected to the coupling boss |42 by the coupling member |44, provides for communication between the port |43 and the square port The valve chamber |4| is also provided with a port |45 which is oppositely disposed with respect to the port |43, and is connected by coupling members |46 and |41, a pipe |48, and coupling members |48 and |50 with the right hand end of the cylinder I5. The end of the outwardly extending portion |40 has asleeve |5I threaded therein which is locked in adjusted position by a nut |52. The outer end of the sleeve I5| is closed except for adsmall relief aperture |53 which extends therethrough for preventing the building lup of apressure or vacuum in the end portion of the valve chamber I4| which would interfere with the operation of the mechanism therein. An adjustment slot for the reception of a screw driver is likewise provided in the end of the sleeve I5I.

A pendulum control valve |55 is mounted in the valve chamber I4I and has an enlarged end portion |56, a spring |51 being interposed `between t-he erld portion |55 and the inner wall oi' the sleeve'|5|. The pendulum valve |55 has a passageway "|58 for alinement with the ports |43 and |45, the other end of the valve rod |55 being slotted or grooved as at |59 for disposal in the forked portion |35 of the pendulum member |35.

The position of the pendulum |35 will determine the positioning of the pendulum valve |55 so that when the vehicle is lev'el or is inclined downwardly the pendulum |35 will be in a. position such that communication will be established through the passageway |58 between the ports |43 and |45 (note Fig. 8). When the vehicle is inclined upwardly, the pendulum |35 will move the pendulum valve |55 to a position such that communication between the ports |43 and |45 will be cut off (see Fig. 4). It will be noted that the pendulum member |35 and the pendulum control valve 55 move. very readily and that a chattering action of the pendulum control valve may occur.

The mode of operation of the system will now be pointed out.

The elbow 86 is in communication with a suitable source of suction, such as the intake manifold 88 of-the engine.

When the operator of the car desires to utilize the apparatus, the handle 91 on the dash board 98 is pulled out to move the dash board control valve member S2, to the proper position so that Athe passageway |01 connects the port 8| with the port |06.

With the dash board control valve member 92 positioned as just referred to, two characteristic modes of operation are possible in accordance with the positioning of the vehicle. In one type oi operating condition the vehicle is level and in the other the vehicle has the forward end inclined upwardly on a hill.

The operating condition when the car is level l will be considered first. If it is desired to utilize the apparatus, the operator. by and upon the release of the accelerator pedal I|`| effects actuation of the accelerator control valve ||5 so that that valve is moved to a position as shown inv Figs. 1, 7 and 12.

Advacuum is thus applied against the left hand side of the piston 35 through the port |06 in the valve housing 80, the passageway I2| in the accelerator control valve I|5, the port ||0 and the passageway |25 in the boss 8| in communication with the left hand end of the cylinder I5. 'I'his vacuum is maintained so long as the valves 32 and I|5 are in the position shown in Fig. 7. The piston 35 accordingly tends to be drawn by the vacuum toward the yleft hand end of the cylinder I5 against the force of the spring 44. As the piston 35 moves to the left the piston rod connected thereto likewise moves Vto the left 4and lthe end of the piston rod is pulled away from the head 5| of the compensator valve 58. against the force of the spring 58, and admits air through the apertures 52, the passageway 41, and the openings 48, to the right hand end of the cylinder I5. .f

y'I'he forces acting on the piston 35 move the piston tothe left and the forces acting through the piston rod 40, the sleeve 50, the spring 58, the rod 82. the rod 53, the clevis' 54 and the rod 55 connected to the brake system 55, 51. accordingly effect an applying of the brakes. The compensator valve may be held open to admit air during the movement of the piston 35 in applying the brakes `and may also be held open during the ytime the brakes are held applied, the action of the valve 50. being determined bythe setting of the spring 88.

The brakes as thus applied will remain in the applied condition so long as the vacuum is maintained at the left hand end of the cylinder |5 whether by the continuous running of the engine, or the operation of the check valve 89.

When it is desired to release the brakes applied as aforesaid, the accelerator pedal II'I is pressed, and the movement thereof through the rod I|5 moves the accelerator control valve I I5 to a position where it first shuts off the vacuum theretofore effective through the ports |05 and I0. Air

is admitted through'the passage |04, the chamber |03 and the groove |22 to the port I|0. It will be noted that the forward end of the groove |22 is designed to permit a gradual flow to the port IIO if a gradual brake releasing action, under the control of the operator, is desired. Upon the admission of the air from the port ||0 through the conduit |25A to the left hand end of the cylinder I5, air at atmospheric pressure is applied against the left hand face of the piston 35. This tends to move the piston towards the right, as shown in the drawings, aided by the spring 44, and the right hand end of the cylinder I5 is connected to the atmosphere through the pendulum control valve I and its fluid connections. It will be noted that upon a slight forward4 movement of the car the pendulum will be caused to oscillate and this movement of the pendulum will be communicated to the pendulum control valve |55 and cause the valve to oscillate or chatter by reason of the swinging of the pendulum when such movement occurs. Any tendency of the pressure at the right hand end of the cylinder I5 to increase unduly will also be prevented by the opening of the atmospheric check valve 23, and the exhausting of air therethrough from the right hand side of the piston 35 to theatmosphere. The brakes are accordingly released under the control of the operator.

The other condition of operation referred to above is that in which the forward end of the car is facing upwardly on a hill. When it is desired to apply the brakes, this is accomplished. as

before, by releasing the accelerator pedal |I'I. A

analisi side thereof, moves agalnstftheforce ofthe spring- Il vtowards the left and/asfpointed outgabove. applies vthebrakes. s f

L Thebrakea `hen,appliedin are held in applied*position` untilreleased by the s operator-.of the .vehicle ashereinafter pointed out.` It isto be noted` that v.the `most diiiculties in `the startingof a .vehiclaarise whenl the vehicle is facing upfahill'andwiththe brakes l.applied and the present invention is vparticularly advantageous in this connection; l. f i

K When it is desired to'release the brakes with the vehicle in the position just referred to, this is accomplished by depressing `the accelerator pedal |`|1 and -moving the accelerator control valve I|| 5to a position to admit air to the left hand end oi the cylinder l5 through the passageway |04, .chamber |03, groove |22, Iport ililkand passageway |25l Asl soon as there is any tendency at the right hand end of the cylinder Ififor pressure to buildup, the atmospheric check valve 23 opens and releases thev air" therethrough to thev atmosphere.",` Y ,K s

Thefpendulurn andthe control valve |55 actuated therebyby reason of theinclination of the lvehicle,'hastakenr a position so that the port |43 is cut olf from communication with the port |45, and no air is permitted to pass the pendulum control valve |55 in this condition. n

If the vehicle is inclined downwardly, the op erations which occurare substantially the same as when the vehicle is'on the level, and `this condition of operation need'not therefore be pointed out lin detail. y n

The controll byA the pendulum control valve |55 is of particular importance in connection with the uid flow withrespect to the right hand end of the cylinder l5, the flow being eiected by the chattering movement in lsmall increments. so that a step by step` movement ofthe piston, rather than a sudden movement thereof, is effected. It

will be noted that if the atmospheric check valve 23 isset to open relatively easily and the spring |51 which controls the oscillatoryl or chattering movement of the pendulum control valve |55 is set relatively loose so that the chattering action is influenced less by the spring 51, and the valve |55 is not held open as long a time, the amount of fluid discharged from the cylinder by way of the pendulum control valve |55 will be relatively smaller, and a more rapid and less smooth brake releasing action will be obtained. If, on the other hand, the atmospheric check valve 23 is set or adjusted so that a somewhat higher pressure is required before this valve 23 opens, and the spring |51 is set relatively tight so that the valve |55 is influenced more by the spring |51 to open position, then a larger quantity of iiuid will be discharged by Way of the pendulum valve |55 and a somewhat slower and smoother brake releasing action will be obtained.

The setting oi the spring 68 of the compensator valve 60 will determine the ease of admission of passageway |08 in communication with the port |05. It will be seen that, irrespective of the position of the accelerator control valve ||5, no

suction will be applied to the left hand end of the cylinder I5, air at atmospheric pressure will be admitted to and exhausted from both ends of the cylinder I5, and the piston 35 will move freely in the cylinder I5 and not interfere with the ordinary and conventional application and release of the brakes.

1. A control system for automotive vehicle brakes comprising a cylinder, a piston therein connected to the vehicle brake system, and means for controlling the movement of the piston including a valve responsive to the inclination of the vehicle and a valve actuated with the accelerator pedal of the vehicle, said last named valve having a passageway for connecting the cylinder at one side of said piston to a vacuum and having a passageway for connecting the same side of said cylinder to the atmosphere.

2. A control system for automotive vehicle brakes comprising a cylinder, a piston therein connected to the vehicle brake system, and means for controlling the movement of the piston, said means including a valve, a pendulum for actuating said valve, and a valve actuated with the accelerator pedal of the vehicle, said last namedvalve having a passageway for connecting the cylinder at`v one side of said piston to a vacuum and having portions for connecting both portions of said cylinder to the atmosphere.

3. A control system for automotive vehicle brakes comprising means for applying and releasing the brakes, and supplemental means for holding the brakes applied and for releasing the brakes under the control of the operator, said means including a cylinder, a piston therein connected to the vehicle brake system, and means for controlling the movement of the piston including a valve, a pendulum responsive to the upward inclination of the vehicle for actuating said valve, an accelerator pedal, and a valve actuated with the accelerator pedal of the vehicle, said valve having a passageway for connecting the cylinder at one side of said piston to a vacuum and having a passageway for connecting the same portion of said cylinder to the atmosphere.

4. In a control system for the brakes of an automotive vehicle, the combination of a cylinder, a piston therein connected to the vehicle brake system, and means for controlling the movement of the piston including an accelerator pedal, a valve actuated with the accelerator pedal of the vehicle, said valve having a passageway for connecting the cylinder at one side of said piston to a vacuum and having a passageway for connecting the same portion of said cylinder to the atmosphere, said valve also having a passageway for connecting the other side of the cylinder to the atmosphere, another valve, and a pendulum responsive to the upward inclination of the vehicle for actuating said other valve.

5. In a control system for the brakes of an automotive vehicle, the combination with a source of suction of a cylinder. a piston in said cylinder connected to the vehicle brake system, and means for controlling the movement of said piston, said means including a fluid conduit connected to one end of said cylinder, valve mechanism for connecting said conduit with the source of suction or with the atmosphere, a fluid conduit connected to the other end of said cylinder, and oscillatory valve mechanism in said last duit connected to the other end of said cylinder,4

and valve mechanism in said last named conduit responsive to the inclination oi' the vehicle for shutting ofi communication through said conduit.

7. In a control system for the brakes of an-automotive vehicle, the combination with a source of suction of a cylinder, a piston in said cylinder connected to the vehicle brake system, and means for controlling the movement of said piston, said means including a iluid conduit connected to one end of said cylinder, a second fluid conduit connected to the other end of said cylinder, valve mechanism under the control of the operator for controlling the ow oi.' iluid through said conduits, said valve mechanism including passagewaysvfor selectively connecting said lrst named iiuid conduit with the source of suction or with the atmosphere, and other passageways for selectively shutting off communication through said second iluid conduit or for connecting said iluid conduit to the atmosphere, and valve mechanism in said second fluid conduit between the rst named valve mechanism and said cylinder responsive to the inclination of the vehicle for permitting iuid ilow through said conduit or for shutting oil communication said conduit.

8. In a control system for the brakes of an automotive vehicle, the combination with a source of suction of a cylinder, a piston in said cylinder connected to the vehicle brake system, and means for controlling the movement of said piston, said means including a iiuid conduit connected to one end of said cylinder, a second iluid conduit connected to the other end of said cylinder, an accelerator device, valve mechanism through y connected to said accelerator device for controlling iluid now through said conduits under the control of the operator, said valve mechanism including passageways for connecting said ilrst named uid conduit with4 the source oi' suction or with the atmosphere and another passageway for shutting ofi' communication through said second iluid conduit or for connecting said uid conduit to the atmosphere, and valve mechanism in-said second conduit between the .first named valve mechanism and said cylinder responsive to the inclination of the vehicle for permitting nuid ilow through said conduit or for shutting oi! communication through said conduit.

9. A control system for automotive vehicle brakes comprising an accelerator device, and means for controlling the release of the brakes, said means including mechanism connected to the accelerator device and subject to the control of the operator, said means also including a pendulum mechanism operable when the vehicle is level for assisting in the release ot the brakes.

10. A control system for automotive vehicle brakes comprising an accelerator device, and means for controlling the applying and release o! the brakes, said means including mechanism connected to the accelerator device and subject to tli'e control of the operator, said means also including a pendulum mechanism operable when the vehicle is level for assisting in the release of the brakes.

11. A control system for automotive vehicle brakes comprising an accelerator device. means operable with said accelerator device for controlling the applying and releasing of the brakes, and means including a pendulum mechanism operable to modify the control effected by said means and assist in the release oi the brakes when the vehicle is level.

12. A system for controlling the release of automotive'vehicle brakes including an expansible chamber device connected to the brakes, control valve mechanism for said device, an accelerator device to which said valve mechanism is con- -nected, and a pendulum actuated valve mechanism for assisting in the release of the brakes when the vehicle islevel and ineffective when the vehicle is inclined upwardly.

JOSEPH H. COYLE. 

